Design, Synthesis, and Pharmacological Evaluation of Substituted Oxadiazole-Pyridazin-3-One Derivatives as Antioxidant and Antimicrobial Agents

Background: The chemical modification of pyridazinone leads to a potent therapeutic agent. Aims: A series of novel analogues of 4,5-dichloro-6-(substituted-benzyl)-2-(5-mercapto-[1,3,4]- oxadiazol-2-ylmethyl)-2H-pyridazin-3-one have been synthesized. Objectives: The novel synthesized pyridazinone derivatives were docked for possible targets, followed by antimicrobial and antioxidant activities. Methods: The target compounds were synthesized using a nucleophilic substitution reaction. The structures of newly synthesized compounds were confirmed by FT-IR, ¹H-NMR, ¹³C-NMR, mass spectroscopy, and elemental analysis. Results: The novel synthesised compounds were screened for their antimicrobial and antioxidant properties in vitro. Compound 5e showed good antibacterial and antifungal activity with MIC 25 μg/mL and 6.25 μg/mL against all the bacterial and fungal strains and in-vitro antioxidant activity with an IC50 of 51.64. The experimental results were further supported by molecular docking analysis using V-Life Science MDS 4.6 software and the GRIP batch docking method. Conclusion: All the compounds have been evaluated in vitro for antioxidant and antimicrobial activities against several strains of microbes and have shown significant activity. The experimental results were further supported by molecular docking analysis, describing improved interaction patterns.